package com.ruoyi.common.swagger.config;

import java.lang.reflect.Field;
import java.util.List;
import java.util.stream.Collectors;
import org.springframework.beans.BeansException;
import org.springframework.beans.factory.config.BeanPostProcessor;
import org.springframework.stereotype.Component;
import org.springframework.util.ReflectionUtils;
import org.springframework.web.servlet.mvc.method.RequestMappingInfoHandlerMapping;
import springfox.documentation.spring.web.plugins.WebFluxRequestHandlerProvider;
import springfox.documentation.spring.web.plugins.WebMvcRequestHandlerProvider;

/**
 * swagger 在 springboot 2.6.x 不兼容问题的处理
 *
 * @author ruoyi
 */
@Component
public class SwaggerBeanPostProcessor implements BeanPostProcessor {
  @Override
  public Object postProcessAfterInitialization(Object bean, String beanName) throws BeansException {
    if (bean instanceof WebMvcRequestHandlerProvider
        || bean instanceof WebFluxRequestHandlerProvider) {
      customizeSpringfoxHandlerMappings(getHandlerMappings(bean));
    }
    return bean;
  }

  private <T extends RequestMappingInfoHandlerMapping> void customizeSpringfoxHandlerMappings(
      List<T> mappings) {
    List<T> copy =
        mappings.stream()
            .filter(mapping -> mapping.getPatternParser() == null)
            .collect(Collectors.toList());
    mappings.clear();
    mappings.addAll(copy);
  }

  @SuppressWarnings("unchecked")
  private List<RequestMappingInfoHandlerMapping> getHandlerMappings(Object bean) {
    try {
      Field field = ReflectionUtils.findField(bean.getClass(), "handlerMappings");
      field.setAccessible(true);
      return (List<RequestMappingInfoHandlerMapping>) field.get(bean);
    } catch (IllegalArgumentException | IllegalAccessException e) {
      throw new IllegalStateException(e);
    }
  }
}
